Top speed limits at all WA traffic-light intersections will be dropped to 70 kilometres-per-hour across the next two years, as part of a State Government plan to prevent serious crashes.

The move aims to create a State-wide consistent maximum speed limit through the signalised intersections.

Marmion Avenue, Gnangara Road, and Bussell Highway have been named as some of the 66 intersections to be altered this year.

A further 40 will be addressed next year.

Sunrise correspondent Matt Tinney has the details.

See omnystudio.com/listener for privacy information.